Recording apparatus for testing machines



April 3, 1928.

W. J. TRETCH ET AL RECORDING APPARATUS FOR TESTING MACHINES 4 Sheets-Sheet l Filed Dec. 15. 1922 mum,

W- .fimwm @Nmvm. KM.

- ATTORNEYS.

April 3, 1928.

w. J. TRETCH ET AL RECORDING APPARATUS FOR TESTING MACHINES Filed Dec. 15. 1922 4 Sheets-Sheet 2 INVENTORS: I 1110mm I ATTORNEYS.

A ril 3, 1928.

W. J. TRETCH ET AL RECORDING APPARATUS FOR TESTING MACHINES Filed Dec. 15. 1922 4 Sheets-Sheet 3 ATTORNEYS.

April 3, 1928.

W. J.TRETCH ET AL RECORDING APPARATUS FOR TESTING MACHINES Filed Dec. 15, 1922 4 Sheets-Sheet 4 ATTORNEYS.

Patented Apr. 3, 1928.

UNITED STA ES PATENT OFFICE.

WILLIAI J. smell, 0] PHILAD BLIHIA,

m m, ABIIGIO BB T0 mm 310s. rmme um 00., 6] PENNSYLVANIA,

I-(BONDING APPARATUS FOR. TESTING. ncnnus.

KAI, OI

VANIA.

rmmmv'ama, mm more anomaa conrona'rron or 2mm- Applieation filed December 15, 192:. Sci-la ll'o. 007,118.

--Our invention consists of a novel construction of a recording apparatusadapted to be attached to a specimen in a vertical screw or other testing machine, whereby novel means are provided for recording on a chart the deformation which is occurring in a specimen under test as the stress is applied.

It further consists of a novel construction of clamps and a novel manner of securing said clamps to the specimen to be tested in sucha way that the recordin apparatus is supported upon one of said c amps, so that the instrument responds .to any motion or give of the specimen inthe testing machine without in anway afiecting the curve bein made on t e chart.

t further consists of a strut hinged in supporting fingers, thereby allowing the of a novel construction ter to accommodate themselves to any uneven setting of the upper clamp.

hinged strut,

It further consists of a novel a seat in the lower end thereof and a strut ball supported in a cavity carried by the lower fingers, in conjunction with means for allowing said lower fin ers to ad'ust to any setting of the lower clamp, sai ball also actin as a fulcrum for the lower. fingers and t e laterally projecting arm therefrom which form a lever, whereby a universal joint is produced which permits the necessaliy adjustment of 'said lower fingers.

urther consists of a novel manner of mounting, supporting and actuatingthe drum carrying the chart, means bein provided whereby'the drum can be quic y and convenientl detached from-its support for -'a change 0 charts,

It further consists ofa novel construction of a hinged bracket bolted to the frame of d the machine, whereby one standard instrument can be installed on various sizes of testing machines, said hinged bracket afl'o'rdng a novel and convenient appliance'for swinging the instrument in place upon the specimen. x

It further consists of a novel adjustable 5 ring support for the sleeve which carries tiie instrument, whereby the whole instrument is resiliently supported u on the spring, in cases where it is desirab e to reproximity to the upper -mountin move as one self-contained unit, so that the record made on the chart is not afi'ected by i any deformation that machine.

It further consists of novel means for manually actuating the pencil coacting with the chart and a novel construction of a speed change device or interchan ble gearing preferably mounted on the gm stand, so that the speed of the ncil can be altered may occur in a testing to make the curve of t e most suitable size.'

It further consists of a novel construction of a trunnion hook adjustably held upon the threaded stem carried by the lower fin ers, which provides a convenient method 0 adjustment to insure correct deformation readings.

It further consists of a novel arrangement of lower fin rs, a laterall projecting stem, a trunnion ook carried tl iereby a connection therefrom passing over a cave, and again passi over and once around an intermediate horizontal sheave mounted on a vertical, s indle' carrying the drum and chart, sai connection passing thence over a vertically arranged sheave and being con- 'nectedtoawei It further consists of a novel manner of supporting and connecting the interme late horizontal sheave with its spindle; which is detachably connected rum carryin the chart, whereby the drumcan be quick y and conveniently detached for a change of charts.

It further consists of a novel construction of a supporting frame for the drum, chart, indicating device and their adjuncts the framework or housing of the testing machine.

It further consists of a novel construction of a frame having laterally projectin upper and lower arms, in the upper arm 0 which,

to the ,q

. and means for supporting said .frame upon is mounted the spindle for the horizontal intermediate sheave,- which latter is detachably connected tothe upper portion of the drum, the lower portion of said drum having an adjustable bearing mounted on the lower arm of said frame. It further consists of other novel features of construction, all as will be hereinafter fully set forth.

For the purpose of illustrating our invene ti0n,we have shown in the accompanying drawings forms thereof which are at present preferred by us, since they will give in practice satisfactory and reliable results, although it is to be understood that the various instrumentalities of which our invention consists can be variously arranged and organized and that our invention is not limited to the precise arrangement and organization of these .instrumentalities as herein shown and described. V

Figure 1 represents a plan view of a recording apparatus embodying our invention attached to a vertical screw or other testing machine, a portion of the testing machine bein shown in dotted lines.

igure 2.represents a front elevation of Figure 1, a portionof the testing machine being shown dotted. l

Figure 3 represents a'section on line 3-3 .of Figiire 2, showing the relative position of the drum, its chart and the indicating device therefor.

Figure 4 represents on an enlarged scale a perspective view of the supporting frame and its adjuncts with the drum removed.

Figure 5 represents'on an enlarged scale a side elevation of certain of the elements seen at the left of Figure 2, certain of the parts, being shown in section to illustrate the hing- ,ing of the strut and the coaction of the lower end thereof with the ball carried in the lower fingers.

Figure 6 represents on an enlarged scale, a section on line 6+6 of Figure 2, showing the detachable connections for enabling the drum to be quickly and conveniently dctached for a change of the chart.

Figure 7 represents on an enlarged scale, a sectional view partly in elevation on line, 7-7 Figure 2.'

- Figure 8 represents a side elevation partly in section of the right hand end of the lower laterally projecting stem seen in Figures 2 and 4, showing the manner of adjustably mounting the trunnion hook on. said stem; Figure 9 represents a section on line 9-9 Fi e 8. I

' igure 10 represents a side elevation of a modification of the construction, seen in Figure 2. .5

Similar numerals of reference indicate corresponding parts in the figures.-

Referring to the drawings In carrymg out our invention we have shown the same in connection with a vertical screw testing machine seen dotted in Figures 1 and 2, the ends of the'speciment 2 to be 'tested being secured to crossheads as 3 and 4 other types of testing machines than that shown. 7

6 designates an upper clamp, which is s ecuredto the upper portion of the specimen 2 by the set screws 7 and 8 designates the lower clamp secured to the specimen by the setscrews 9, our novel instrument recording the deformation occurring betweem these points of attachment.

10 designates upper fingers which rest at the points 11 upon the upper clamp 6, said fingers being connected to or projecting from the head 12, from which projects laterally the rod 13, which is connected to the sleeve 14, which slides on the rod 15, held by the machine frame. The, frame 16 is secured to the sleeve 14 in any suitable manner and comprises the 'upright member 17 from which projects the upper and lower arms 18 and 19, it being apparent that the whole mechanism including said frame and its ad juncts is supported on the specimen 2.

.At the point 20, see Figures 2 and 5, is

hinged the upper end of the strut 21, having Y on its lower end a concavity or ball seat 22 (see Figure 5) which rests on a steel ball 23,

seated in a chamber in a head 24, which serves as a universal joint and carries the lower fingers 25, which are supported at the points 26 upon the lower clamp '8. The

spring 27 common to the head 24 and the pin 28, projecting from the lower-portion of the strut 21, keeps the ball 23 in proper contact with its seat as will be evident from the lower portion of Figure 5. i 29 designates a rod or long stem projecting laterally from the lower head 24, and functioning as a lever fulcrumed on the ball 23. The outer end of the stem 29 is threaded at 30', and carries the loose sleeve or collar 31,

.having the nuts 32 between which is the trunnion ring 33 pivotally mounted at 33 (see Figures 8 and 9) and having the book 34. secured thereto, to which is fastenedthe lower end of the thread 35, which runs over the sheave 36 supported from the arm 16", once around the intermediate horizontal Inn sheave 37, and thence around the sheave 38,

its end 39 being secured to the weight 40 as best seen in Figures 2 and 4. The intermediate horizontal sheave 37 is mounted on'the upright spindle 41, which is connected to the arm 18, (see'Figure 6) the lower end of said shaft having the conical head 43, which is shaft 42, which has its hearings in thenpper which is in threaded engagement with said head. -The drum is com sed of the u per and lower spiders 46 an 47 carryin t e cylinder 48, against which is secure the chart 49, and from the hub of the lower spider 47 projects the lower bearing 50, which is step ed into the seat 51 of the adjustable mem r 52, mounted in-the lower arm 19, it being apparent that the sheave 37 and the parts 41, 42, 46, 44, 45 and revolve in unison as a unit, the thread 35 being kept tlght by the weight 40, which latter also keeps the fingers 25 hard against the lower clamp 8, and in addition causes the drum 45 and its chart to revolve in proportion to the change in distance between the clamps 6 and 8, when the specimen 2 is tested. 53 designates a screw rotatably mounted in the arms 7 18 and 19 and extending parallel to the drum 45, and carrying the pencil holder 54 and pencil 55, which may be of any suitable construction, and need not be described in detail; The lower end of the screw. 53 is connected with one end of the flexible shaft 56, whose other end is connected at 57 with the upright spindle 58, whose lower ortion has the pinion 59 thereon above which is the gear 60, said gear'and pinion beingadjustable as a unit on the spindle 58 and held in position by the set screw 58*, (see Figure 7). 61 desighates a hand wheel having the handle 62, which is mounted on the shaft 63, which carries the bevel gear 64 in mesh with the bevel inion 65 which is mounted on upright s aft66, which is parallel to the shaft 58 and carries the pinion 67, which is adapted to mesh with the gear 60 when desired and the gear 68 which is adapted to mesh with the pinion 59, it being of course understood. that when the gears 68 and 59 are in mesh (as in Figure 2) the gears 67 and 60 are out of mesh. It will be a parent from Figure 2 that the' rotation -o the hand wheel 61 effects, by the intermediate connections, the rotation of the shaft 66 and by the intermeshing of .the gears 68 and 59 the flexible shaft 56 and screw53 are rotated, thereby moving the encil longitudinally of the chart 49 ast e latter rotates. The speed chan edevice seen at the ri ht hand portion of igures 1 and 2 is pre er-- ably located on the beam stand of the testing machine and when "thegears are in mesh as seen in Figure 2, it will be a parent that a relatively rapid rotation will he imparted to the flexible shaft 56 and the screw 53.- Upon making the pro er adjustments "to-- throw the gears an '67 into mesh and throw the gears 59 and 68 out of'mesh, it will beevident that a relatively-slower rotation wi be imparted to said flexible shaft and screw. The frame 16 carrying the drum and-its adjuncts can be constructed and supported in any suitable manner, but we preferably'tie the outer ends of the arms 18 and";

19 together by the upright rod 69 gsee Fi I ures 2 and 4) and we support the rame 6 from the sleeve 14 and support the upright 77 b means of the u and 1, through whic passes the upright rod 72 which is supported from the arms 73 of the bracket 76 bolted to the frame 74 of the testing machine. c The arms and 71. are connected to the upright 77, (see Figure 4) and the latter has the deflected ends 78 and 79, through which pass the ends of the rod per and lower. arms. 70 I 15, which carry the upper and lower collars 80 and 81. By this construction a standard bracketcan be made to fit various sizes of machines and this hinged bracket connection provides a new and convenient method of swinging the instrument in place on the specimen. In the construction seen inFigure 10 we have shown an adjustable spring support for the sleeve 14, comprising the spr1ng'75", supportedv on the adjustable 'c0l-' lar 7 6", whereby the whole instrument is sup- L ported upon said collar and spring, in cases where it is desirable to relieve the specimen of the weight of the instrument, andto oper-' ate the upper fingers 77" under the upper clamp 6, instead of on the top thereof as seen in Figures 2 and 5'.

The operation is as follows The parts having been assembled as seen inFigures 2 and 5, it will be apparent that thewei ht of the instrument will be supported y the contact of the up r fingers 10 upon the 11 per clamp 6, the wh anism being t us supported upon the specimen 2. The pull exerted-by the weight 40 will be imparted to the outer'en'd of the ole mechlong stem 29, the ball 22 seen in Figure 5 serving as a fulcrum oint, and making a true universal joint, t at allows the lower fingers 25 to adjust to any settin of the lower clamp 8, while the strut 21 a ows the upper fingers to accommodate themselves to any uneven setting of the upper clamp 6.

It will be apparent that the instrument records the deformation occurring between the points of attachment of the clamps 6 and 8 and that as the testing machine is open ated,' the stretch of the specimen 2 wil ,be visually portrayed by the pencil 55 upon the chart 49 during the revolution thereof since any change in the position of thestem 29 will, through the medium of the thread 35 cause the rotation of the sheave 36 and alsoof' the intermediate horizontal sheave 37, which will effect the rotation of the drum 45 and its chart 49.- Simultaneously with the stretchin of thes cimen 2, the oper ator rotates t ehand w eel 61 and by reason of the gears 64 and 65, the shaft 66 willbe rotated together with the gear 68 and thepinion 59. The pinion 59 rotates in unison with the shaft 58, as will be understood from Figure 7, and the] rotation of said ,shaft through the medium of the flexible shaft 56 will effect the rotation of the screw 53, which.

will cause the pencil 55 to move vertically and portray a curve on the chart 49.

It will be apparent that the motion of the pencil in proportion to the stress combined with the revolution of the drum, in proportion to the strain, produces a very accurate stress-strain diagram on the chart 49 fastened around the drum 45 from which the modulus of elasticity can be readily calculated. It will be apparent that by reason of the trunnion 33*, see Figures 8 and 9, and manner of mounting and assembling the trunnion hook 341, and the adjustable nut 32, that the proper or desired multiplication can be obtained with the stem 29. By reason of the employment of the strut 21 and its adjuncts seen in Figure 5 a very accurate operation of the co-acting parts is ensured and by reason of the connections seen in Figure 6, wherein the nut 4:6 is employed,

. itwill be apparent that upon loosening said nut, the drum 45 can be, readily and conveniently detached for the purpose of changing charts.

By the provision of the speed change device seen in Figure 7 and at the right of Figure 2, it will beapparent that the speedof rotation of the shaft 58, and consequently the speed of rotation of the flexible shaft 56 and the screw 53-can be readily altered to suit requirements, so that the speed of the pencil 55 can be alteredto portray the-curve of most suitable size.

By the construction of hinged bracket applied to the frame of the machine, as willbe understood from Figure 4, a standard instrument can be made to fit various sizes of testing machmes and this hinged bracket construction obviously. provides a new and convenient method of swinging the instrument in place upon the specimen 2. In case it is desired to relieve the specimen 2 of the weight of the instrument the adjustable spring support seen in Figure 10 may be employed,'in which case the upper fingers 77 are positioned under clamp 6 instead of on the top thereof as seen in Figure 2: I r

Our invention can be quickly installed in positionand-will accurately record on the chart, the deformation changes occurring in a specimen under test, as the stress is applied.

Having thus described our invention, what lingers, a flexible connection fromisaid stem to' a movable portion of said instrument, forrotating the latter when stress is applied to the specimen to be tested and a drum actifiitedby deflection of said specimen.

2. In a device of the character stated, upper and lower clamps, means for securing said clamps to the specimen to be tested, upper and lower lingers contactingqvith said clamps, an upright strut Hinged at its upper end upon said upper fingers, a ball contacting with a seat, in the lower end of said strut, said ball being carried by said lower fingers, tension devices common to said lower fingers and strut, for holding the latter in contact with said ball, and means for recording any movement of said lower stem'occurring during the deformation of the specimen to be 1 tested as to 

